Logical/IP Addresses

Logical/IP Addresses

The Logical/IP addresses scheme is the backbone and base of computer communication. For worldwide communication a need was felt to have a unique identification of all the devices, for the said purpose addressing scheme was developed so that each device can be identified uniquely.

Logical/IP addresses are assigned only by the IANA(Internet Assigned Number Authority) although if a network is not connected to the internet that network can determine its own numbering.

The existing version now-a-days IP VER-4 and contains 32 bits.

A new version of IP (contain 128-bits), called IP VER-6 or IPng (IP next generation) can handle much larger headers.

The IPv6 is a new standard IP protocol going to replace IPv4 in the near future.

The Logical/IP addresses have been divided into different classes. In that the A, B and C are used for computer communication, the D is use for multicasting and E class is used for research purpose. The ranges of these classes are also discussed below.

IP Address Classes & Class Ranges of Internet Addresses (IP)::

The following are IP Address Classes:

Class A 0————–To———-127

Class B 128———-To———–191

Class C 192———–To———-223

Class D 224———–To———-239

Class E 240———–To———-255

Class A:

The Class A addresses is explained as:

The 1st bit of Network id is 0.

The Range of the Class A members are from 0.0.0.0 to 127.255.255.255

The No’s of Possible ‘s of valid hosts can be given using formula 2n-2

Note: such addresses where all the host bits are “0s”, these are the network addresses, that we can’t use, e.g. 10.0.0.0 & such addresses where all the host bits are “1s”, these are the broadcast addresses, which we can’t use. e.g. 10.255.255.255

Class B:

Class Baddress is explained as:

The first 2-bits of Netid are one and zero (10).

The Range of the network numbers is from 128 to 191 can be written as 128.0.0.0 to 191.255.255.255

The No’s of Possible Networks: 214 = 16, 384 b/c of 10. Because the 2 bits in 16 bit are reserved so that’s why we take power of 14 instead of 16.

The No’s of possible IP in the host portion: 2n = 216 = 65, 536, where n is number of variable/host bits. The 16 is the remaining no’s of Bit.

Note: such addresses where all the host bits are “0s”, these are the network addresses, that we can’t use, e.g. 172.14.0.0 and such addresses where all the host bits are “1s” these are the broadcast addresses, which we can’t use. e.g. 172.14.255.255

Class C:

Class Caddresses is explain as:

As the first 3-bits of Netid are 110 and the first 3 bits are reserved.

Number of possible values in the host portion: 2n = 28 = 256, where n is number of variable/host bits.

Note: such addresses where all the host bits are “0s”, these are the network addresses, that can’t use, e.g. 192.168.100.0 &

Such addresses where all the host bits are “1s”, these are the broadcast addresses, which we can’t use. e.g. 192.168.100.255

Subnet Mask:

The Masking is actually the process that extracts the address of the physical network from an IP address. Masking can be done whether have subnetting or not. If the network id’s is submitted then the masking extracts the subnetwork address from an IP address.